Upright short-lived perennial that grows 12-36 inches tall. Has hairy leaves and stems with three leaflets per leaf. Has pink or lavender flowers, and a taproot. There are medium (double-cut) and mammoth (single-cut) types. Medium types flower the year they are seeded and regrow vigorously after cutting. Mammoth types grow slower, maturing about 2 weeks later than medium types. Mammoth types require vernalization to flower and tolerate drought better than medium types.
Matt Ruark and Dan Smith – University of Wisconsin